The present invention relates to the field of fluid recovery systems, especially in soils. The invention applies for example to the recovery of gas but also liquids, in particular in aggregates such as soils, sediments, waste, etc. In general, the invention applies to any type of fluid which can be present in aggregates and can be implemented in soils in general, for example under works, such as retention ponds or construction foundations, in landfill waste or in sediments of various types.
Geocomposites and laminar products intended for drainage applications, comprising at least one layer or draining layer and at least one layer of watertight material are known from the prior art, especially from the applications of patent FR2746424 and U.S. Pat. No. 4,733,989. However, these solutions have the disadvantages of not allowing sufficiently efficacious fluid recovery and not resolving some problems in the field of fluid recovery.
A first problem in the field of fluid recovery systems relates to the fact that it is generally difficult to recover fluids present in aggregates, in particular when the aim is to recover gases. For example, gas recovery systems comprising wells and/or trenches made within waste for collecting gases which escape from the latter especially during decomposition of organic waste are known in waste landfill of the prior art, especially in buried landfill. These systems have the disadvantages of being costly and complex to put in place, as they need to provide wells and collecting trenches within waste during burying of the latter. In addition, the recovery of gases generally takes place only around wells and trenches, whereas a non-negligible quantity of gas can reach the surface of the landfill, which creates problems, of pollution especially. Similarly, in the field of building or public works, and in general in various types of works, the problem of the recovery of gas arises frequently, especially under water retention ponds or under construction foundations. In fact, water retention ponds are arranged on a support watertight to liquids and construction foundations are generally arranged on a support impervious to water and/or gas (such as a membrane made of polyane or polyethylene, for example) or are arranged directly on the soil (or the sub-soil in the case of excavations). It is frequent for gas to rise from depths of soils and their accumulation under the works presents risks for the latter.
A second problem, which also arises in the fields of waste and constructions, relates to the fact that known gas recovery systems are generally not adapted to the recovery of liquid. For example, the wells and trenches used in landfill are arranged for the recovery of gas, but liquids which penetrate here flow to the bottom and need to provide additional devices specific to their recovery. The gas recovery system therefore needs to be complemented by a liquid recovery system, which has disadvantages in costs and execution complexity.